Congrats maxim you have already found the holy grail of dashcams, that be the one with the least trade offs.
There are a constant influx of people wanting things that's not there yet, or have too high hopes for things that appear to be there now.
I myself have dropped a lot of what i thought was good ideas for future dashcams, some have been shot down in the first subsequent post on the forum, but a few have also been noted by progressive manufactures i am sure.
I can also follow the people that have their new car dinged all the time, even with my very casual relationship to my car also suffer to some degree.
But as it is now guarding your parked car are somewhat of a roll of the dice, i do like the concept of the idea but i have not yet found it worthwhile to pursue.
So what i would do is just put a power bank on one of my cameras and then record all the time, but so far i have not felt like that was needed with the places i visit.
It is a little the same with the number of dashcams in a car, sure i have 4 or more at any given time in my car, not that i think its needed but i am a tester, and i like to expose idiots in traffic on youtube, and if thats the case you cant really have too many cameras.
But for day to day coverage and documentation of what go on Vs the silly BS some one will say to try and get off doing something illegal, well then i think the one camera in the windscreen will work fine in most cases, and if you are really paranoid then add a rear camera too.
But the side cameras like i also have, well those are really overkill and it is pretty rare i resort to those in my youtube uploads as most of the really idiotic stuff go on in front of my car or behind it.
So the footage of my side cameras are really just icing on the cake som times, and also as it are single cameras i use each with its own memory card then mixing them up in post production are a bit of a mess due to time stamps never really being in sync.
BUT ! as many of us in here sink deeper and deeper into the abyssal of dashcams and idiot drivers we go to extremes, so some of us now also have a camera on the windscreen with a "zoom" lens, giving us a better view of what go on way ut ahead whish regular dashcams struggle with due to the wide angle lenses in use.
Zoom VS regular.
Side camera captures on a good day. ( all driving 80 km/h highway speed at least )